Because of her circumstances, Woman 1 makes a deal with the System. In ancient times, she meets Woman 2, and the two become intertwined and fall in love. Woman 1 believes their meeting is fate, unaware that they were already lovers in a past life. The System, too, is nothing more than an obsession left behind by her previous life. In that life, Woman 1 believed that Woman 2 had died saving her, and that grief took shape as an obsession, which became the System. It also became the god and system of countless small worlds. In the end, driven by its obsession and desire to resurrect its beloved, the System prepares to sacrifice countless worlds. The story's secondary couple were also lovers in a past life, but the rules of their sect led to Man 2's death. Man 1 followed the last remnant of Man 2's soul into this small world, where the two can stay together for the rest of their lives.
Theme: Love has no gender. Perhaps your fates have been turning around each other since long ago.